1. Field of the Invention
The present invention generally relates to solid state illumination devices, and particularly to illumination devices using solid state light emitting diodes (LEDs).
2. Description of Related Art
Solid state LEDs are widely used, such as in illumination devices or non-emissive display devices, due to high brightness, long lifespan, and wide color variety.
Illumination devices such as Christmas lights or rainbow lamps typically include a mounting base and a solid state LED mounted thereon. The solid state LED includes a substrate, a transparent material, a wafer, and positive and negative electrodes. The wafer is encapsulated in the substrate by the transparent material and electrically connects with top ends of the electrodes. Bottom ends of the electrodes extend through the substrate and are inserted into receiving holes defined in the mounting base. The bottom ends of the positive and negative electrodes electrically connect with positive and negative power supply electrodes located in the mounting base, electrically connecting the wafer to the power supply electrodes.
During assembly of the illumination device, the positive and negative electrodes need to electrically connect to the positive and negative power supply electrodes, respectively. A process for distinguishing the positive and negative electrodes is thus needed. However, the positive and negative electrodes have substantially the same configuration, complicating the process and prolonging the assembly time. Therefore, an illumination device is needed to address the described limitations.